Neither the font, nor the spacing looks to be "factory". If a vehicle was titled using the "engine number" it was not uncommon for a replacement engine to have the ID ground off and the original code restamped. It wasn't technically "legal" to do that in some places, but most shops, especially independent ones, just didn't care. A 1948 216 I have in my shop right now has the number stamped on the front of the gasket surface for the pushrod cover, as well as on the machined pad behind the distributor. Both the font and the spacing appear to be factory numbers.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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